Electrical and Computer Engineering EventsEvents from the AJ Clark School of Engineeringhttp://eng.umd.edu/events/
Thu, 08 Dec 2016 16:40:25 ESTElectrical and Computer Engineering Eventshttp://eng.umd.edu/images/clark_logo_4email.gifhttp://eng.umd.edu/events/
Ph.D. Dissertation Defense: Dakang MaTuesday, December 13, 2016 5:30 PM, ERF 1207 (IREAP, large conference room), ANNOUNCEMENT: Ph.D. Dissertation Defense
Name: Dakang Ma
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Committee:
Professor Jeremy N. Munday, Chair
Professor Christopher Davis
Professor Thomas M. Antonsen
Doctor Henri Lezec (NIST)
Professor Raymond Sedwick, Dean's Representative
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Date/time: Tuesday, Dec.13th, 2016&nbsp;/ 10:30am-12:30pm
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Location: ERF 1207 (IREAP, large conference room)
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Title: Measurement of radiation pressure and tailored momentum transfer through switchable photonic devices
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Abstract:Light carries momentum, which can be transferred to an object upon reflection or absorption. The resulting force per unit area from light, so called radiation pressure, is rather weak but can have macroscopic consequences. For example, sunlight imparts momentum on dust particles causing a comet's tail to be directed away from the sun. In a microscopic world, micro/nano-mechanical transducers have become sensitive enough that radiation pressure can influence them greatly. However, photothermal effects, often accompany and overwhelm the radiation pressure, complicating its measurement. In this thesis, we first show a quantitative measurement of the radiation force on an uncoated silicon nitride microcantilever in an ambient condition. We identify and separate the radiation pressure and photothermal effects through an analysis of the cantilever's frequency response. Further, we demonstrate the first measurement of a wavelength-dependent radiation pressure due to optical interference in a silicon microcantilever. We utilize in-situ optical transmission measurement at the excitation position to determine the local optical properties.
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Another interesting application of radiation pressure is a solar sail. Solar sails use solar radiation pressure as propulsion and offer an opportunity for propellant-free space travel, enabling long-term and long-distance missions that are impossible with traditional methods. Although solar sail propulsion alleviates the need to carry chemical fuel, attitude control and steering are still performed using traditional methods involving reaction wheels and propellant ejection. In the second part of the thesis, we present a steerable solar sail concept based on a polymer dispersed liquid crystal (PDLC) device that switches between transparent and scattering states, enabling attitude control without mechanically moving parts or chemical propellant. Devices are fabricated and characterized (transmission, reflection, absorption and scattering) over the visible and near infrared range of solar spectrum (400 nm - 1100 nm) and are found to outperform previous designs by more than a factor of four in terms of over-all weighted momentum switchablility between on and off states. Devices require no power in the diffusely reflective state and dissipate less than 0.5 mW/cm^2 while in the on state, showing great potential as a low-power switching mechanism for solar sail attitude control.
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&nbsp;http://www.ece.umd.edu/events/index.php?mode=4&id=12025
http://www.ece.umd.edu/events/index.php?mode=4&id=12025Ph.D. Dissertation Defense: Tiecheng ZhuWednesday, December 14, 2016 3:00 PM, AVW 2460, ANNOUNCEMENT: Ph.D. Dissertation Defense
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Name: Tiecheng Zhu
Committee:
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Professor Mario Dagenais (Chair)
Professor Chris Davis
Professor Martin Peckerar
Professor Thomas Murphy
Professor Sylvain Veilleux (Dean's Representative)
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Date/Time: Wed, December 14, 2016 at 10:00 am&nbsp;
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Location: AVW 2460
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Title: &nbsp;Layer Peeling/Adding Algorithm and Complex Waveguide Bragg Grating For Any Spectrum Regeneration &amp;&nbsp;Fiber-to-Waveguide Coupler With Ultra High Coupling Efficiency
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Abstract:&nbsp;
A Layer Peeling/Adding algorithm for designing optical filters is not only developed theoretically but also demonstrated experimentally. Unlike the conventional design approaches which can handle only limited spectral profiles, the algorithm presented here is capable of regenerating transmission/reflection spectra of any shape. As a proof of demonstration, Complex Waveguide Bragg Gratings (CWBG) are designed, fabricated and characterized using the algorithm. The CWBG, which is implemented as a single-mode Si3N4/SiO2 waveguide grating with aperodic varying waveguide widths, is capable of removing a large number of randomly-distributed wavelengths simultaneously. Two generations of CWBGs are shown to remove 20 and 47 notches, with spectral precision better than +-0.1 nm, suppression ratios larger than 15 dB, and 3-dB width of 0.3 nm. Among the CWBG's various potential applications, we highlight its use for eliminating the OH emission lines from the Earth's atmosphere for ground-based astronomical observations.
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An easy-to-fabricate but very efficient fiber-to-waveguide coupler is theoretically analyzed and experimentally demonstrated. In this design, light from a single-mode fiber can be butt-coupled into a single-mode high-index-contrast Si3N4/SiO2 waveguide with a measured coupling efficiency of 96 % at the wavelength of 1550 nm, and &gt; 90 % in the spectral range from 1450 nm to 1650 nm. Large horizontal and vertical alignment tolerances of 3.8 um and 3.6 um respectively are obtained between the fiber and the waveguide coupler. All these experimental results agree well with simulations. The waveguide coupler also features ease of end-facet cleaving, and can be used in ultra-broadband high coupling efficiency applications.&nbsp;--
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http://www.ece.umd.edu/events/index.php?mode=4&id=12026
http://www.ece.umd.edu/events/index.php?mode=4&id=12026Ph.D. Research Proposal Exam: Qinyi XuFriday, December 09, 2016 4:30 PM, Jeong H. Kim Engineering Building 2211, ANNOUNCEMENT: Ph.D. Research Proposal Exam
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Name: Qinyi Xu
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Committee:
Professor K. J. Ray Liu (Chair)
Professor Min Wu
Professor Gang Qu
Date/time: December 9th, 11:30 a.m.
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Location: Jeong H. Kim Engineering Building 2211
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Title: Smart Radio for Indoor Monitoring and Human Recognition
&nbsp;http://www.ece.umd.edu/events/index.php?mode=4&id=12031
http://www.ece.umd.edu/events/index.php?mode=4&id=12031Work Visas, OPT, & Green Cards in the Job SearchThursday, December 08, 2016 10:00 PM, 1110 Kim Engineering Building (Lecture Room), Confused about options for staying and working in the United States after graduation? Worried about the H1B quota? What about the STEM extension for OPT?
Presented by attorney Mark Rhoads of the law firm McCandlish Holton.
Topics will include a detailed discussion of the H1B visa, which is the most popular work visa in the US, Optional Practical Training (OPT), and options for pursuing permanent residence through employment. In addition, Mark will provide practical strategies for talking to employers about work visa issues during interviews.http://www.ece.umd.edu/events/index.php?mode=4&id=12014
http://www.ece.umd.edu/events/index.php?mode=4&id=12014Whiting-Turner Lecture: Michael ArmaniThursday, April 27, 2017 9:30 PM, Lecture Hall, 1110 Kim Engineering Building, Details forthcoming.
To register for this FREE event, visit:&nbsp;http://go.umd.edu/2017W-TArmani&nbsp;http://www.ece.umd.edu/events/index.php?mode=4&id=12030
http://www.ece.umd.edu/events/index.php?mode=4&id=12030Distinguished Scholar Teacher Lecture: Hugh Bruck "Bioinspired Engineering: From Icarus to Robo..."Thursday, December 08, 2016 9:00 PM, Kay Boardrooms, DISTINGUISHED SCHOLAR TEACHER LECTURE
Speaker: Hugh Bruck Associate Chair Director of Graduate StudiesProfessor, Mechanical Engineering University of Maryland
Bioinspired Engineering: From Icarus to Robo Raven
December 8, 2016 | 4:00 PM | Kay Boardrooms, Jeong H. Kim Engineering Building&nbsp;
As engineers, we often use mechanics to understand motion, and materials science to manipulate matter to solve problems through novel structural solutions, such as strong, lightweight composites that can withstand the large aerodynamic forces needed for fixed wing aircraft and rotorcraft to fly. However, in nature, mechanics and materials often comes together in a variety of unique ways that we can have fun learning from. One of the most interesting is found in birds, where flexible, lightweight wings combine with powerful small muscles to generate aerodynamic forces much greater than their body weight by &ldquo;flapping&rdquo; and controlling their wing shape. However, this has been a challenge for us to duplicate in flying vehicles, where conventional composite wings are designed to be significantly more rigid to keep their shape as they are propelled through the air by motors. Recently, we have developed a new bio-inspired flapping wing air vehicle (FWAV) known as &ldquo;Robo Raven&rdquo;. It is capable of achieving flight in the same way birds do: by controlling their shape during flapping. This was accomplished through a new understanding of how to design flexible wing structures and to passively deform them through powerful, lightweight, and compact servo motors that can be programmed to act like muscles. While birds served as &ldquo;biological inspiration&rdquo; for Robo Raven, we have also been able to investigate the use of new materials, such as flexible solar cells and batteries, which we integrate into wings to harvest solar energy, store it, and sense the wing deformations generated by aerodynamic forces, resulting in new &ldquo;multifunctional bio-inspired structures&rdquo;. Thus, by adopting new paradigms as engineers where we learn from nature, we have been able to create FWAVs that are more autonomous and interact synergistically with their environment, just like real birds! &nbsp;
More info at: www.enme.umd.edu/events/seminarshttp://www.ece.umd.edu/events/index.php?mode=4&id=12034
http://www.ece.umd.edu/events/index.php?mode=4&id=12034ME Seminar: Dawn M. Tilbury "Virtual Fusion: Combing Simulations with Operations to Improve... Saturday, October 21, 2017 7:00 PM, DeWalt Seminar Room, 2164 Martin Hall, Dawn M. Tilbury, Ph.D.Associate Dean of ResearchProfessor, Mechanical EngineeringUniversity of Michigan"Virtual Fusion: Combing Simulations with Operations to Improve Manufacturing System Control"Abstract: Revolutionary computing technologies are driving significant advances in the manu facturing domain. High-fidelity simulations and virtual design environments allow unprecedent ed opportunities to test and validate systems before they are built, reducing overall design time and cost. Big Data streaming from the factory floor can be collected over high-speed networks, and stored in large-scale server farms (such as cloud-based systems). Comparison of key perfor mance indicators between the expected or simulated system and the actual physical system can enable improved analytics, leading to increased performance. This talk will describe how the integration of simulation and plant-floor data can enable new control approaches that are able to optimize the overall performance of manufacturing systems.
Link to flyer [PDF].http://www.ece.umd.edu/events/index.php?mode=4&id=11932
http://www.ece.umd.edu/events/index.php?mode=4&id=11932Effective Interviewing WorkshopThursday, December 08, 2016 3:00 PM, 1131B Glenn L. Martin Hall, Are you ready for your next interview for an internship or full time job? How should you prepare? What qualities/skills might recruiters test in your interview? What should you wear and bring? This session examines these expectations, provides information on what you can do now to prepare for future interviews, and reviews typical interview styles and questions.&nbsp;&nbsp;
Bring a pen to take notes.
Space limited to 30 students.
See the fall career workshop calendar.
RSVP for this workshop to receive a reminder.
&nbsp;http://www.ece.umd.edu/events/index.php?mode=4&id=11889
http://www.ece.umd.edu/events/index.php?mode=4&id=11889Booz Allen Hamilton Colloquium: Thomas Richardson, VP, Engineering, Qualcomm Inc.Friday, December 09, 2016 8:00 PM, 1110 Jeong H. Kim Engineering Building , http://www.ece.umd.edu/events/index.php?mode=4&id=11941
http://www.ece.umd.edu/events/index.php?mode=4&id=11941Ph.D. Research Proposal Exam: Hongyu XuTuesday, December 20, 2016 3:00 PM, Rooms - 4424 AVW Bldg., ANNOUNCEMENT: Ph.D.&nbsp;Research&nbsp;Proposal&nbsp;Exam
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Name: Hongyu Xu
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Committee:
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Professor Rama Chellappa (Chair/Advisor)
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Professor Larry S. Davis
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Professor Behtash Babadi
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Date/time: Tuesday, December 20th, 2016 at 10:00AM
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Location: AV Williams Conference Rooms - 4424
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Title:&nbsp;Learning Dictionaries for Face Recognition and Object Classification
http://www.ece.umd.edu/events/index.php?mode=4&id=12053
http://www.ece.umd.edu/events/index.php?mode=4&id=12053